Each year an estimated 100 children and adolescents die of a farm-related injury; another 100,000 children suffer a nonfatal injury associated with agricultural production. Despite the plethora of surveillance data to document these injuries, few analytic studies have focused on agricultural injuries in children; none in a southern state. Farming operations with livestock, especially cattle, have been identified from surveillance data as associated with a higher risk of injury for workers compared with other commodity farms. However, the work tasks, exposures, and potential risk of injury to children on beef cattle farms remain largely undocumented. We propose a three-year longitudinal cohort study of children living and working on family owned and operated farms in the state of Kentucky. The primary intent of the study will be to fully characterize the work tasks and exposures of these children-an estimated 41 percent of whom live on beef cattle farms-and to explore a diverse set of potential injury risk factors- particularly developmental characteristics of the child, parental influences, and farm management practices-for children residing on these farms. Baseline data were collected in 1994/95 on a cohort of children (N=999) living on family farms from 60 counties across Kentucky as part of the NIOSH Kentucky Farm Family Health and Hazard Surveillance Project, a multi-mode effort to determine agricultural risk and injuries among farm families in Kentucky. Beginning in the summer of 2000, children aged 5 to 18 years old will be reinterviewed by parental or guardian proxy, with repeated assessment every six months of all injury events which require medical attention or treatment or lead to a loss of time at work or school. The cohort of 999 children will be stratified into two agricultural commodity groups-those who live on farms where the primary commodity is beef cattle and those on other commodity farms (tobacco, grain). The study will examine selected child characteristics (physical size, risk perception family role) and parental influences (supervision, prohibitions on work tasks, and assessment of the child's ability) as risk factors for agricultural injuries. In addition, detailed data collection efforts regarding farm management practices, including cattle, handling procedures and characteristics of confinement facilities, are planned for the beef cattle farms. The study is intended to provide needed data for the formulation of age and developmentally appropriate guidelines for children's work on beef cattle farms and ideas for engineering and technologic improvements regarding cattle handling procedures, the design of equipment (e.g., headgates) and confinement facilities for these farms.